/**
 * 加载时调整文件
 * 适用webpack 4.XX.XX
 */
module.exports = function (source, map) {
  this.cacheable();

  var query = this.query;

  var prepend = query.prepend || '';
  var append = query.append || '';

  source = prepend + source + append;

  this.callback(null, source, map)
};
